/**
 * @Author Big_white
 * @Date 2021/11/11
 */
public class Stereo {
    private static Stereo instance=new Stereo();
    public static Stereo getInstance()
    {
        return instance;
    }
    public void on(){
        System.out.println("Stereo on");
    }
    public void off(){
        System.out.println("Stereo off");
    }
    public void up(){
        System.out.println("Stereo up.....");
    }
}
